Google Sketchup is a user friendly program, that only takes minutes to understand and be able to work with. There are even dozens of tutorial videos, guides, and even websites to teach you and help you master the program. Using Google Sketchup, one can design and create unique and new things such as key chains, models, instruments, and so much more.
Google Sketchup is a free download, and is suitable to most peoples needs. However, there is a Google Sketchup Pro program, however this will cost you a pretty penny. Rounding at about 500 dollars, here's what you can have:
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If you have trouble learning how to use Google Sketchup or Google Sketchup Pro, there is a "warehouse" of files for Google Sketchup that you can access. This "warehouse" is a place where people share their creation and allow others to have it. (http://sketchup.google.com/3dwarehouse/)